zzkt/osc
1
0
Fork 0
Code Issues 7 Pull requests Projects Releases Activity Actions

Reuse uint decoders when possible

Browse source 
The int decoder does the same work as its corresponding uint decoder
before encoding the integer in Two's complement. We can re-use the
uint decoder instead of writing the same code in the corresponding int
decoder.
This commit is contained in:
Javier Olaechea 2019-03-24 16:14:43 -05:00 committed by nik gaffney
parent 26c7107ad3
commit 2924fe75e0
Signed by: nik
GPG key ID: 989F5E6EDB478160
1 changed files with 28 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

28
osc.lisp
View file

@ -352,6 +352,7 @@ with the current time use (encode-timetag :time)."
(ldb (byte 16 0) (decode-int32 s)))
#-(or sbcl cmucl openmcl allegro) (error "cant decode floats using this implementation"))
<<<<<<< HEAD
(defun decode-int32 (s)
"4 byte -> 32 bit int -> two's compliment (in network byte order)"
(let ((i (+ (ash (elt s 0) 24)
@ -362,6 +363,8 @@ with the current time use (encode-timetag :time)."
(- 0 (- #x100000000 i))
i)))
=======
>>>>>>> d130e45 (Reuse uint decoders when possible)
(defun decode-uint32 (s)
"4 byte -> 32 bit unsigned int"
(let ((i (+ (ash (elt s 0) 24)
@ -370,6 +373,18 @@ with the current time use (encode-timetag :time)."
(elt s 3))))
i))
(defun decode-uint64 (s)
"8 byte -> 64 bit unsigned int"
(let ((i (+ (ash (elt s 0) 56)
(ash (elt s 1) 48)
(ash (elt s 2) 40)
(ash (elt s 3) 32)
(ash (elt s 4) 24)
(ash (elt s 5) 16)
(ash (elt s 6) 8)
(elt s 7))))
i))
(defmacro defint-encoder (num-of-octets &optional docstring)
(let ((enc-name (intern (format nil "~:@(encode-int~)~D" (* 8 num-of-octets))))
(buf (gensym))
@ -388,6 +403,7 @@ with the current time use (encode-timetag :time)."
(defint-encoder 4 "Convert an integer into a sequence of 4 bytes in network byte order.")
(defint-encoder 8 "Convert an integer into a sequence of 8 bytes in network byte order.")
<<<<<<< HEAD
(defun decode-uint64 (s)
"8 byte -> 64 bit unsigned int"
(let ((i (+ (ash (elt s 0) 56)
@ -410,6 +426,18 @@ with the current time use (encode-timetag :time)."
(ash (elt s 5) 16)
(ash (elt s 6) 8)
(elt s 7))))
=======
(defun decode-int32 (s)
"4 byte -> 32 bit int -> two's complement (in network byte order)"
(let ((i (decode-uint32 s)))
(if (>= i #x7fffffff)
(- 0 (- #x100000000 i))
i)))
(defun decode-int64 (s)
"8 byte -> 64 bit int -> two's complement (in network byte order)"
(let ((i (decode-uint64 s)))
>>>>>>> d130e45 (Reuse uint decoders when possible)
(if (>= i #x7fffffffffffffff)
(- 0 (- #x10000000000000000 i))
i)))